Economically, the high-IQ misanthrope has an even weaker case. Smart people may excel in all activities, but as the law of comparative advantage reveals (see here and here) everyone's better off if people with high IQs outsource their less challenging tasks to others. In a society of Einsteins, Einsteins take out the garbage, scrub floors, and wash dishes. What a mind-numbing waste of talent!
Caplan’s argument is correct on its own terms, obviously, but is fundamentally useless because the assumptions it rests on are largely inapplicable to the real world. There is no society of Einsteins, which I take to mean a society of super-intelligent people, defined as, say, possessing an average IQ of 2+ standard deviations above the global mean. Assuming, for fun of course, that PISA scores from 2009 are generally indicative of a given country’s overall level of intelligence,* it’s clear that while some countries’ populations are smarter than other countries’ populations, it’s not quite the case that there are nations filled to the brim with Einsteins who would be setting out to cure cancer if only they didn’t have to take out the trash.
In the first place, intelligence is not the only variable that has any bearing on solving problems. Luck/chance/randomness all play a role in finding solutions to various problems (see here, here, here, and here, for starters), as does funding, equipment, and access to other forms of capital. Perhaps this is assumed in Caplan’s model, but it is nonetheless worth remembering that merely throwing a bunch of smart people at a problem is no guarantee of success. It’s also worth remembering that some smart people need to provide things for dumb people (like food, shelter, clothing and all that) in order to pay other smart people to solve smart people problems. At any rate, on a micro level at least, is simply not the case that having all the smart people free to solve problems is a guarantee of any sort of solution, though the odds of a solution being found do improve.
In the second place, though, Caplan makes the unsubstantiated assumption that stupid people are needed to relieve smart people of their less-challenging tasks. There are several things wrong with this assumption, the foremost of which is that the division of labor is always and forever a good thing, such that each person should specialize in just one thing, and never bother to do anything other than that which they specialize in, save for those tasks which are necessary for day-to-day living (eating, bathing, etc.). This is a slight exaggeration, of course, but the broader point—that doing any sort of menial labor somehow precludes or otherwise interferes with smart people solving challenging problems, is simply ludicrous. On a micro level, handling menial tasks does not preclude an intelligent person from solving other problems. For example, cooking one’s own meals does not necessarily interfere with one’s cancer research. Even time dedicated to pursuing one’s particular specialization is subject to the law of diminishing returns.
But the other, and far more stupid, assumption is that smart people are unable to solve the problem of menial labor. Yes, some tedious work is always going to have a significant time component. And menial labor that is always based on a time component (like babysitting, e.g.) cannot necessarily lead to time-saving innovations. However, problems like garbage collection have been made more efficient over time due to the invention and innovation of labor-saving devices. Raw production has been made more efficient due to innovations like the assembly line and automation. In these cases, smart people have found ways to save on labor by making capital more useful. The easiest way to do this, though, is to a) be smart and b) have some familiarity with the labor process you are trying to improve. Thus, the case for stupid people working menial jobs is not as obvious as it might seem, since it might be the case that labor improvements in menial work arise from “Einsteins” learning a menial process and taking time to figure out how to improve it.
An obvious example of this, at least to me, is that of Japan. Japan has a relatively intelligent population with low numbers of less-intelligent immigrants. Clearly, Japan is not lacking for technical innovation, and their relative absence of cheap, “dumb” labor does not seem to lead to trash piling up in alleys and a massive number of deaths from typhoid. The Caplanesque response to this question-begging would obviously be to rejoin with, “and now imagine how much better off they would be if they had dumb laborers doing this work for them, instead of having their Einsteins waste time innovating menial processes.” But this hypothetical rejoinder is more indicative of one’s worldview (and is logically circular to boot) than it is of the facts on the ground. Plus, the obvious reply to the hypothetical Caplan response would be, “but would they have had more or better innovation anyway had they focused on improving more complex processes?” Again, throwing bodies at a problem doesn’t ensure its solution, and innovation of any sort has diminishing returns.
When all is said and done, though, the question of whether cheap, “dumb” labor is wealth-enabling is mostly a matter of ideology, not facts, since it is impossible to know how much wealthier a country would be in the absence (or presence) of more “dumb” labor. Thus, arguing for or against an increased amount of cheap, “dumb” labor is mostly indicative of one’s ideology than of practical reality because ultimately the answer is unknowable.
Thus, it can ultimately be asserted that Caplan is arguing for a sort of new aristocracy—complete with an underclass—that consists of highly intelligent people solving important, smart-people problems, who are to be served by dumb, low-skilled workers. At least the society of Einsteins, of which Caplan is surely a part, will not have their important research interrupted by such banal trivialities like garbage disposal and dish-cleaning. Their technocratic problem-solving will undoubtedly usher the world into a new era of peaceful prosperity, and it’s all thanks to cheap, dumb labor.
* An extremely dubious claim, to be sure, and one made here only for the sake of argument.